The Croak of a Different Frog

Southern Leopard Frog (Rana sphenocephala)

That One Sounds Different

If you ever listen to the croaking of frogs, you know they can be symphonic and beautiful. If you have the chance listen carefully, and see if you can hear differences in the croaks. Some subtle differences will be between individuals, but if you hear big differences, then you are probably listening to more than one species. Kind of cool, huh? Just as different birds have different calls, different frogs have different croaks, and it was this knowledge and a keen ear which led to the discovery of a new species in what people thought was a well-studied area.

In case you are not in an area where you can hear frogs, here's a clip. Listen carefully and you'll hear the Northern Leopard Frog (Rana pipiens), the Grey Tree Frog (Hyla versicolor) and the American Toad (Bufo americanus).

No Duh's and Head Scratchers

If you need help scratching a mental itch, use the resources below:

Were you aware that different species of frogs could be identified by their croaks? If not, does this surprise you? What kinds of purposes do you think these croaks serve? What kinds of information would you need to gather to test your hypothesis?

How were researchers able to confirm their suspicion that there was an undescribed species of frog? What problems could they have run into if they didn't have this sort of information? Why is this sort of information hard to argue with?

Notice the patterns researchers used when collecting specimens to test. Why do you think they chose this pattern? Can you think of any other information they could gain by using this pattern beyond species differences?

What roll do you think knowledge of different species should play in urban development plans? Do you think it is important to have different species of frogs or is one species enough for ecosystem stability? What kinds of information would you consider in making your decision? Do you think you would reach the same decision in all areas?